The present technology relates to an error detection and correction apparatus, a mismatch detection apparatus, a memory system and an error detection and correction method. In particular, the present technology relates to an error detection and correction apparatus for detecting and correcting an error in data read out from a non-volatile memory, a mismatch detection apparatus, a memory system and an error detection and correction method.
In a recent information processing system, an NVM (non-volatile memory) will be used as an auxiliary storage device or storage. Examples of the non-volatile memory include a flash memory, a ReRAM (Resistance RAM), a PCRAM (Phase-Change RAM) and an MRAM (Magnetoresistie RAM). In the non-volatile memory, recorded data may be broken due to a thermal noise and may not be read out correctly. For this reason, a data storage device generates an ECC (Error detection and Correction Code) from data to be recorded to record it on the non-volatile memory. The data storage device can detect and correct a data error based on the ECC when data is regenerated.
In the error detection and correction, there is proposed a system where data is read out a plurality of times using different threshold voltages, each data is compared to detect erasure, and correct an error based on the erasure detected (for example, see United States Patent Application Publication No. 2010/0077279).